<form name="form1" action="zkoiuskajs.html">
<input type="text" name="vklad" id="vklad" value="" >
<input type="button" name="tlac" value="pocitej" onClick="areaOfCircle(vklad.value);return false;">
</form>
<script type="text/javascript">
function areaOfCircle(radius)
{
Vysledek = Math.PI * Math.pow(radius, 2);
return document.write("\n\n<br><br>Výpočet " + Vysledek);
}
</script>